Abstract: A planar diaphragm loudspeaker incorporating a planar diaphragm having multiple sound producing regions, a support frame, and one or more electromagnetic drivers coupled to the sound producing regions on the rear surface of the diaphragm. A first sound producing region is formed generally centrally on the rear surface of the diaphragm, and second and third sound producing regions are formed on opposite sides thereof. The sound producing regions comprise raised portions on the rear surface of the diaphragm which are symmetrical about both first and second orthogonal axes for balance. Cross members extend between opposite sides of the support frame so as to overlay all of the sound producing regions to selectively mount separate electromagnetic drivers for coupling to each sound producing region, as well as to mount one or more anchors extending from the cross members to the perimeters of the second and third sound producing regions in order to isolate them from the first sound producing region.

Abstract: A planar-type loudspeaker incorporating a substantially planar diaphragm constructed from a pre-expanded cellular plastic material, such as polystyrene, in which separate portions of the diaphragm have different densities. The higher density portion is designed for the reproduction of high frequencies, and the lower density section is used for the reproduction of low frequencies. In one embodiment, the diaphragm is formed by laminating together a pair of diaphragm members having the different densities to define a single sound producing region, to which a single voice coil assembly is coupled. In another embodiment, the diaphragm is formed as a unitary, one-piece structure having separate but contiguous sound producing regions, each with its own density material and voice coil assembly for reproducing a specified frequency range of sound.

Abstract: A planar-type loudspeaker incorporating a substantially planar diaphragm constructed from a pre-expanded cellular plastic material, such as polystyrene, in which separate portions of the diaphragm have different densities. The higher density portion is designed for the reproduction of high frequencies, and the lower density section is used for the reproduction of low frequencies. In one embodiment, the diaphragm is formed by laminating together a pair of diaphragm members having the different densities to define a single sound producing region, to which a single voice coil assembly is coupled. In another embodiment, the diaphragm is formed as a unitary, one-piece structure having separate but contiguous sound producing regions, each with its own density material and voice coil assembly for reproducing a specified frequency range of sound.